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Criterion Traveller

Temperature Rating :

Many influences can affect temperature ratings of sleeping bags using a similar level of down fill weight and fill power such as construction/baffle types, size/dimensions of the shell, fabrics, amount of down used in the hood, foot and zip & neck baffle sections. But also the differential fill i.e. relative proportions of fill of down used in the top and bottom sections of bag can have a significant bearing on the thermal efficiency. The temperature rating on the Criterion sleeping bags is a figure at which an average, experienced camper using a tent and good quality mat would feel comfortable at.

The rating is based on many years manufacturing experience, field trials and supported by independent tests at Leeds University. Although as you are aware many varying factors can affect comfort levels whilst sleeping not least the perception of comfort and warmth of the user.